Guiding unit for reproducing machines



May 30, 1944. F. c. GEIBIG 2,349,954

GUIDING UNIT FOR REPRODUCING MACHINES Filed April 18, 1942 2 Sheets-Sheet 1 N 0 l /5 day? 8 11 o I INVENTOR 6'5 x o FRANK C. GEIBIG ATTORNEY y 1944 F. c. GElBlG 2,349,954

GUIDING UNIT FOR REPRODUCING MACHINES Filed April 18, 1942 2 Sheets-Sheet 2 g: 57 Z2 v 25 as 7/ 62 6'5 72 25 54 3/ 54 m \Y/ Q llllll v P .INVENTOR FRANK C. GEIBIG ATTORNEY.

Patented May 30, 1944 GUIDING UNIT FOR REPRODUCING MACHINES Frank 0. Geibig, Westfleld, N. 1., assignor to The Linde Air Products Company, .a corporation of Ohio Application April 18, 1942, Serial No. 439,479

22 Claim.

This invention relates to guiding mechanism and more particularly to tracing devices for controlling the motion of the tool-supporting carriage of a reproducing machine.

It has been customary when reproducing contours, to mount a reproducing tool, such as a flame-cutting blowpipe, on a carriage free to move in all directions in a plane, and to guide the carriage along a path defined by a templet located on a working surface. The carriage customarily has been propelled and guided by traction wheels which either engage the opposite sides of a templet strip or roll directly upon a paper pattern as shown in S. R. Oldham Patent No. 2,279,338 dated April 14, 1942.

In many cases, the path to be followed consists of a number of straight lines having included angles of known degree. Even with such simple shapes it has been customary to prepare a drawing to serve as an outline for a hand-guided traction unit, or to prepare a mechanical templet consisting of a bent strip along which driving trunnions may roll. Both of these practices entail an expediture of time, labor, and materials that may be dispensed with completely through the medium of the present invention. If it is desired to use a paper templet in conjunction with a manually-guided traction head, unnecessary wear of the templet may be avoided by means of the present invention, thereby considerably extending the templet life.

The principal objects of the present invention are: to provide an improved guiding device for a reproducing machine; to provide a templet tracing device that minimizes wear of paper templets,

or the like, and thereby extends their useful life; to provide means for preselecting a desired angular movement of a tool-supporting carriage while the tool is moving in a different direction, and thereby to expedite a change in the direction of travel when the need for such change arises; to provide improved cooperation between an angle selector for a tool-supporting carriage, and an odometer adapted to indicate the extent of the carriage travel. These and other objects of the invention will become apparent from the following description and from the accompanying drawings disclosing one form of the invention as applied to the upper carriage of a shapecutting machine of the type shown in S. R. Oldham Patent No. 2,279,338 dated April 14, 1942. In the drawings:

Fig. 1 is a perspective view of the improved tracing device as applied to the upper carriage of a shape-cutting machine;

Fig. 21s a vertical cross-sectional view through the guiding unit, with parts in elevation, showing the relation of the unit to the traction head of a shape-cutting machine;

Fig. 3 is a transverse sectional view taken on the line 3--3 of Fig. 2 showing the dial and locking mechanism of the guiding unit;

Fig. 4 is a longitudinal sectional view through the tracingwh'eel column taken on the line 4-4 of Fig. 2;

Fig. 5 is a detail sectional view of the selfregistering latch for the guiding unit taken on the line 5-5 of Fig. 3;

Fig. 6 is a vertical sectional view through the angle selector lock taken on the line 6-4 of Fig. 3;

Fig. '7 is a semi-diagrammatic view of the odometer transmission; and

Fig. 8 is an enlarged sectional view through a portion of the odometer transmission taken on the line 8-8 of Fig. 7.

Generally speaking, the invention comprises a combination of an odometer D connected in an improved manner to the propelling means or traction head P of a reproducing machine so as to record total carriage travel. An improved guiding unit G controls the direction of carriage motion and is provided with an angle selector 8 capable of providing a quick change of travel from one direction to another. An improved odometer transmission N operates the odometer in a single direction irrespective of whether the carriage propulsion is in a forward or reverse di-= rection.

The odometer or distance indicator D is shown in Fig. I mounted upon the tool-supporting carriage C of a shape-cutting machine of the type shown in Oldham Patent No. 2,279,338 dated April 14, 1942, although the apparatus obviously is adapted for use with contouring machines generally, irrespective of the nature of the carriage support or the type of reproducing tool employed. The carriage C is mounted for movement in varying directions in a plane, e. g., along rectangular coordinates over a horizontal work surface or traction surface provided by the top of a table T. It will become apparent, however, that the movement need not be limited to any particular plane, and that the use throughout the present description of terms denoting horizontal, perpendicular, or other positions of the parts is to be construed in a relative sense only. Forward and reverse buttons B control the circuit of a drive motor M and provide forward and reverse motion of the traction wheel Wt.

The transmission V is provided with driving means rotatable in opposite directions, such as a reversible drive shaft H.- The shaft ii is provided with a driving connection I? such as a bevel pinion, which pinion is rotatable either in a clockwise or counterclockwise direction depending upon whether the forward or reverse button B has been depressed. A pair of driving members such as bevel gears l3 mesh with and are rotated in mutually opposite directions by the driving connection I2.

The odometer D connects with the bevel gears I 3 through a shaft l6 and a gear train It having a gear ratio selected to provide odometer readings in selected units of carriage travel. for example, inches or millimeters. In order to provide readings of the odometer in a single direction, irrespective of the direction of rotation of the connection l2, the shaft l forming part of the odometer transmission system is operable in a single direction by whichever of the drive members i 3 rotates in the direction chosen for the rotation of the shaft IS. The unidirectional rotation of the shaft i5 is effected by means of clutches l6, each of which is capable of driving the shaft l 5 in but a single direction, e. 7., clockwise when facing the left end of the shaft, as indicated by the arrow in Fig. 8. Any type of clutch or equivalent mechanism may be employed for the purpose, typical of which is the ball clutch disclosed in Fig. 8. Such a clutch comprises a driving ring I! secured to and rotatable with the gear l3. A wedge plate l8, splined to the shaft l5, transmits motion from the ring I! through one or more balls l9, wedged between elongated slots 2| and the inner periphery of the driving ring I! during clockwise rotation of the ring. The gear l3 that is rotating in a counterclockwise direction, slips freely on a loose journalled connection between it and the shaft l5. Accordingly, it is apparent that the odometer always is operated in the same direction by the oppositely rotatable shaft it through the unidirectionally operable clutches l6 and shaft I5.

The guiding unit G is secured to the carriage C by a bracket 22 integral with the traction head P or by other suitable means. Although the functions of the guiding unit G may be incorporated in the traction head P, some additional advantages are provided by separating the two, as shown in Figs. 1 and 2. A housing or support 23 encloses and protects the guiding unit G and provides a base on which to mount the various parts. Essentially, the guiding unit G comprises a manually-operated steering column for controlling the direction of travel of the traction wheel Wt at a point separated from the traction head P. The steering action through predetermined angles is facilitated by the angle selector S which permits setting'up the desired angle in advance.

A steering column 24 is journalled within the housing 23 preferably with spaced antiiriction bearings 25. The column 24 may be steered by a suitable manual control such as a handle 26, preferably in the form of a knob, handwheel, or spider. The handwheel is located in a position readily available to the operator, and if desired may be secured to a flanged head 21 at the top of the column 24. An upwardly extending rim 29 extends about the head 21 for engagement with the handle 26 about an annular zone, the parts being held tightly together by a machine screw 28 threaded axially into the column 24.

The slight cavitation in the head 21 provides firmer frictional engagement between the handle 28 and the rim 29 precluding relativemovement between the parts during ordinary operation. If it is desired to adjust the handle relatively to the column 24, the screw 28 may be loosened.

The steering motion of the handle. is imparted to the traction wheel Wt by positive interlocking connections between the steering column 24 and a rotatable sleeve 3| within the traction head P. As shown in Fig. 2, such connections may comprise identical gears 32 and 63 locked to the steering column 24 and rotatable sleeve 3! respectively, each of which meshes with an idler gear 64. Accordingly, the steering motion imparted to the column 24 is transmitted to the sleeve 81 and produces an angular change of the same magnitude and direction in the position of the traction wheel Wt.

The angle of traction wheel travel may be indicated by a suitable cooperating scale and index denoting the angular relationship between the handle 28 and the housing 23 or other reference body, and accordingly the direction in which the carriage travels. As shown in Figs. 1 and 3, use may be made of a calibrated ring or protractor scale 85 screwed or otherwise attached to a radial flange 37 on the handle 26. A suitable index or reference mark 38 may be made in any convenient place on the housing 23. It will be apparent from Fig. 1 that a separate or alternative calibrated ring or scale 35' may be formed directly about the housing 23, and that an index d3 may be made to rotate with the handle 26 as will appear.

The apparatus thus far described forms an operative unit by itself and may be employed in the following manner without the remaining parts to be described. The shape to be followed is charted in terms of distances and angles, and the carriage motion is controlled by coordinating the readings of the odometer and of the protractor scale. As a simple example of operation, let it be assumed that a 2" x 4" rectangle is to be formed. The carriage is guided in any convenient direction until the odometer indicates a travel of 4". Referring to his chart, the operator observes that at this point the handle 26 is to be shifted this is done manually with the aid of the scale 35, and the carriage permitted to travel in the new direction until the odometer reading indicates a total of 6". Again referring to the chart, the operator alters the course by a second 90 movement of the handle 26 until the odometer reading is 10", at which time the last turn is made to complete the rectangle.

If desired, a guide wheel or tracing wheel We may be freely rotatably mounted at the bottom of the steering column 24 for rolling engagement with a sflitable templet 39 laid or drawn directly upon the traction surface of the table T. Such a wheel may be relatively small and narrow with a smooth peripheral edge as compared with the relatively large and thick traction wheel Wt having a knurled edge for increased tractional effect. The axis of the guide wheel W9 is correlated relative to the axis of the traction wheel Wt, e. g., so that both wheels are directed in parallel paths. The guide wheel Wg thus may be made to follow about the path of the templet 39 to assist the operator in coordinating the angle and distance readings, or the guide wheel Wg may be used exclusively to direct the direction of travel in accordance with the templet contour.

Substantial advantages reside in using sepaalmanac rate guide and traction wheels in that by having the guide wheel of smaller dimensions, the wheel may be maintained more easily on the desired a path. Furthermore, the roughened or knurled edge of the traction wheel thereby does not fola low the contour path as in normal practice, but is free to move directly on the traction surface T or about margins of the templet 39, thereby eliminating the concentrated wear along the templet path that is destructive to the templet. The guide wheel Wg rolls freely on the surface and the smooth surface does not erode the templet as does a positively driven traction wheel.

The construction of the guide wheel Wu and of the means employed for mounting it at the ill bottom of column 24 is clearly shown in Fig. 4. Wheel-mounting means 4i comprises a bearinf 42 having a slotted lower extremity for rotatably receiving the wheel We. The bearing 42 is slidably connected with respect to a bearing support 43 to provide a limited vertical floating action of the wheel relative to the bearing support along a line perpendicular to the traction surface. Aithough the bearing and wheel may slide downwardly against the templet under the natural 25 influence of gravity, use preferably is made of additional means, such as a compression spring 44 urging the guide wheel vertically downward against the traction surface. The bearing is stopped at the lower limit of its range of floating movement as by a pin 45 extending through the surrounding wall of the bearing support es, en gaging the end of a vertical groove 46 in the bearing 42. 1

The entire wheel-mounting assembly M is adjustably movable vertically on the steering column 24 to locate the bearing support 63 at the proper elevation to cooperate with the traction surface T. As shown in Fig. 4, an adjust-= able screw 47 cooperates with a vertical keyway 48 in the side of the column 24 so as to preclude relative angular motion between the bearing support 43 and the column 24. The bearing support 23 may be held at the desired elevation by locking the parts together with a locking screw dd. The screw 49 may be used as a rough adjustment to position the parts relative to the height of the table T, whereas the floating movement between the parts 42 and 43 may compensate for irregularities in the traction surface.

Wheel adjusting means in the form of a swivel clamp joins the upper and lower sections of the bearing support 43. The clamp 5| may be integral with either of the sections, and is shown integral with top section. By loosening the clamp 5|, the lower section, and accordingly the wheel Wg, may be pivoted relative to the scale 35 on column 24 into predetermined angular relation with respect to the traction wheel Wt.

A source of illumination 52 such as one or more electric lights may be disposed above the wheel Wg to illuminate the templet path. A shield 53 reflects the light downwardly onto the templet and protects the operator from glare.

Although the operator may hold the handle 26 continuously during the tracing operation, more accurate results may be obtained in tracing straight lines by locking the steering column in position for movement along the successive desired angles. A steering lock 54 is provided for this purpose in the manner shown in Figs. 1, 2, and 3. A locking lever 55 may be pivotally mounted within the housing 23 for frictional engagement with an inner peripheral edge 56 of gig the radial flange 37. A relatively light spring ti? may be employed to urge the lever 55 into the releasing position. The lever 55 may be pressed into locking engagement by an actuator comprising a threaded rod 59, the inner end at which is socketed to receive a hardened steel ball 53 bearing against the lever 55. A locking knob 82 pivots in opposite directions to move the rod 59 in and out of the housing 23 a sufiicientdistance to engage and disengage the lock. The extreme positions of movement may be indicated on the outside of the housing as shown in Fig. i, and a pointer 63 may extend from the knob 82 to denote whether the lock is engaged or not. A look nut 34 holds the knob in fixed position on the rod 59 and allows relative adjustment between the parts to compensate for wear.

It may be desirable for the lock to be urged continuously into the engaging position so that the wheel We will continue in a selected direction whenever the knob 52 is released. A spiral spring 65 may be located in a cavity he of the knob $2, with the ends of the spring engaging the knob and housing 23 respectively. Thus, with the knob under initial tension, the threaded rod 59 will be urged inwardly at all times to secure the steering column 24 in selected position. A latch may be utilized to hold the lock in the disengaged position, such mechanism comprising a spring detent 61 adapted to engage a recess did in the knob 5h The detent 6! has suiiicient strength to hold knob 52 in the leased position against the action of the spiral spring 65 To expedite the operation of turning corners, an angle selector means S has been provided by which the desired angular change may be set up on the machine in advance, so that the agtual turning operation becomes a substantially instantaneous mechanical step free of personai error. The angle selector S operates on the prin ciple of locating a stop or latch at the desired angle while the carriage is approaching a corner, so that at the moment the corner is reached, the guiding mechanism may be swung into a registering position relative to the selector means-to accurately locate the traction wheel for the carriage motion in the new direction. Although any suitable angle setting mechanism might be employed for this purpose, the present embodi ment utilizes a selector ring 69 resting on and rotatable about a radially extending flange Ii surrounding the housing 23. The ring 69 may be held against removal by an annular locking plate 12, fastened to the housing 23 in position to overlap an inwardly extending flange on the ring 69. The ring 69 encompasses the calibrated ring 35 and provides an ideal location on its top surface for the index mark 38, by which the relative angular position between the ring 69 and the steering column 24 may be determined. The parts are in normal position relative to one another when a zero reading of the ring 35 is aligned with the index 38, as shown in Figs. 1 and 3. To provide more accurate location of the parts in the normal position, use is made of a self-registering latch 13 extending from the ring 69 for locking engagement with the steering column 24, preferably by cooperation with the flange 31 of the handle 26. As shown in Fig. 5, such a latch may comprise a latch body 14 having a wedge-shaped locking element 15 urged inwardly against the flange iii as by a compression spring 16. The locking element wedges itself against the sides of a vertical it formed in the periphery of the ring 31 so as to secure the ring 31 and flange 68 against relative motion. The latch may be disengaged from the slot ll by means of a knob 18, and the latch may be held in the disengaged position by pivoting the knob until a stop 30 rests against the end of the body 14 so as to restrain the locking element from moving inwardly. Accordingly, it will become apparent thatif the parts are moved from the normal position with the stop 80 disen aged, the locking element I5 will snap into the locking position as soon as it registers with the slot 11. If the zero reading of the calibrated ring 35 should deviate from the indexes 33 when the latch 13 is in the locked position, the parts may be brought into alignment by loosening the screw 28 and turning the handle 26 as required, while the steering column is locked by knob 62.

The selector ring 69 may be fixed with respect to the housing 23 by means of a selector-ring lock 19. A simple form of lock suitable for this purpose is shown in Fig. 6 and comprises a clamping lug 81 that may be tightened against the lower surface of the flange II by a thumb screw 82 extending downwardly through a boss III on the ring 69 into threaded engagement with the lug 8|.

The selector ring may be located in predetermined relation to the housing 23 as by means of one or more cooperating indexes or marks ill and 84. These marks preferably are so located that when they are aligned, the angle selector and steering column are in the normal position, and the traction wheel is directed in a predetermined direction, for example, in a direction defined by one of the rectangular coordinates along which the carriage C moves. Normally, this direction extends parallel with either the lower or upper rails of the carriage C. Ii use is made of the calibrated ring 35', the mark 814 preferably constitutes the zero position thereof.

In operation, the angle selector S may be set in the normal position relative to the steering column, and the marks 33 and 84 aligned and the ring 63 locked in this position if the first line to be traced extends along one of the rectangular coordinates of the carriage motion. This ordinarily is arranged for by locating the templet 33 (if one is used) in such a position on the table T' that the first straight line to be traced extends transversely of the table T. The steering column 24 is locked in this position by engaging the 1 steering lock 54 so that the traction wheel is precluded from deviating from the line, and the carriage is set in motion. By referring to his chart, the operator determines the angle to be turned when the guide wheel Wg reaches the first corner. The angle selector ring 69 is then shifted from the normal position shown in Fig.1 through an arc corresponding to the desired angle by disengaging the latch 13 and the selector ring lock 19, until the index 38 coincides with the desired angle on the ring 35. The stop 80 is released allowing the element I5 to abut the periphery of the flange 31 and the lock I3 is engaged to hold the selector ring in the new position. At the instant that the guide wheel Wg reaches the corner, the steering lock 54 is released and the handle 26 rotated in the direction that the ring d3 was turned, until the parts again register in the normal position by engagement of the latch 13 with the slot ll. The carriage then proceeds in the new direction, during which time the operator may again set the angle selector for the next required angle change. The operator may determine when t6 shift the steering mechanism by reference to the odometer reading exclusively, or by observing the position of the guide wheel Wg, though in many cases the odometer reading will provide a more accurate indication. A reset mechanism on the odometer may bemanually operated to set the odometer at a zero reading at the beginning of each operation. If the operator desires, the odometer may be reset when each corner is reached, in which case the distance along the component lines of the contour are registered individually; By using the scale 35' and the index 83, the angles through which the ring 89 are hifted may be determined as absolute angles referred to a datum'line, such as one of the rectangular coordinates of carriage motion, rather than as included angles between adjoining segments of the templet path.

It will be observed that gie angles indicated on the selector ring are determined in part by the direction of the traction wheel travel, that is, whether the car'riage is traveling in a forward or reverse direction. To compensate for this, duplicate protractor scales may be provided on the ring 35, as, shown in Fig. 3, which scales are out of phase. Distinguishing marks such as the marks F and R may be inscribed in proper position on the scale to designate forward and reverse travel respectively, so that the proper zero mark might be located adjacent to the index 38. Preferably, however, two marks 83 are employed in diametrically opposite positions on the ring 59, as shown in Fig. 2. These likewise may be identiiied by distinguishing characters to advise the operator which of the two is to be aligned with the index 84 according to whether the carriage is operated in a forward or reverse direction, in which case a single protractor scale 35 is sufficient.

It may be desired to have the angle selector S operate automatically to swing the steering column through the desired angle. Although any form of apparatus may be employed for this purpose, a simple type of construction illustrating the idea is shown in Fig. 6. The automatic shifting means comprises a coiled tension spring 86 extending along a peripheral groove 81 located partly in the flange 31, and partly in the ring 69. The ends of the spring are secured to the flange 31 and ring 69 respectively, so that when the parts are shifted from the normal position the spring is extended, and held in the extended position when the parts are secured by the selector lock 19. When the corner is reached, the steering lock 54 is released, and the spring 86,swings the steering column 24 through the selected angle until the latch 13 registers with the slot 11.

By keeping the latch 13 engaged and the lock 19 disengaged, the index 83 and the scale 35 may be utilized in conjunction with the odometer to guide the machine without preselecting the angles. Similarly, the latch 13 may be permanently disengaged and the lock 19 engaged to permit guiding the machine with the scale 35 and index 38. By having the lock 54 urged continuously into the engaged position, the operator need not think about looking the steering column after a corner has been turned. It will be apparent that while the angle selector S has been shown in coniunction with a separate guiding unit G, the principles of the invention may be incorporated directly in the traction head P.

Various modifications oi the herein-disclosed inventionmay be made by those skilled in the art, without departing from the principles of the invention or sacrificing its advantages.

I claim:

1. In a machine of the character described which is provided with an odometer, a guiding unit, and a tool carriage; the combination of oppositely-rotatable driving means for propelling said carriage respectively in forward and reverse directions; a unidirectionally-operable odometer transmission extending from said oppositelyrotatable driving means for operating said odometer in one direction irrespective of the direction of carriage movement; and angle selector means for said guiding unit adapted to determine the direction in which said carriage is propelled, while the distance in that direction is indicated by said odometer.

2. In a machine of the character described which is provided with an odometer, a guiding unit, and a carriage; the combination of a reversible drive shaft for propelling said carriage respectively in forward and reverse directions; odometer-driving means comprising a pair of drive members operated in mutually-opposite directions by said drive shaft, and a unidirectionally-operable transmission connecting with said pair of drive members and operable by whichever of the members is rotating in a given direction, whereby said odometer registers alike the forward and reverse motion of said carriage, said guiding unit comprising manually adjustable steering means and angle selector means for said steering means to determine the direction in which said carriage is propelled, while the distance in that direction is indicated by said odometer: and means for locking said angle selector means to maintain said direction. I

3. A reproducing machine comprising a toolsupporting carriage relatively movable in varying directions over a traction surface; a traction head having a traction wheel in rolling engagement with said surface; and a manually-com trolled guiding unit operatively connected with said head for steering said traction wheel over said surface, said guiding unit having a freely rotatable guide wheel for rolling engagement with a templet on said surface, the axes of said respective wheels being so located as to direct said wheels along parallel paths.

4. A reproducing machine as claimed in claim 3 wherein said traction wheel has a knurled peripheral edge to increase the tractional effect, and wherein said guide wheel has a relatively narrow, smooth, peripheral edge to assist in aligning said guide wheel with the contour of said templet.

5. A traction-head guiding unit for reproducing machines of the type having a tool-supporting carriage relatively movable in varying directions along a traction surface by a steerable traction wheel rotatably mounted on said head for rolling engagement with said surface, said guiding unit comprising a support on said carriage in spaced relation to said head: a guide wheel journalled relative to said support for free rolling contact along said surface; manually operable steering means for steering said uide wheel along a predetermined course; and interlocking connections between said guide wheel and said traction wheel whereby the steering motion of said guide wheel is imparted to said traction wheel, whereby both of said wheels are steered in unison to guide said carriage along a path defined by said course.

6. A guiding unit for the traction'head of a reproducing machine or the type having a toolsupporting carriage propelled in varying directions in a horizontal plane along a course simulating a templet path on a traction surface by a steerable traction wheel in rolling engagement with said surface, said guiding unit comprising a support adapted to be secured to said carriage; a steering column swivelled to said support; positive connections extending between said column and said traction head, whereby rotary motion of said column controls the steering of said traction wheel; a tracing wheei iournalled at the lower end of said column for rolling engagement along the templet path on said surface; a manually operable handle for swiveling said column; and an adjustable swivel joint between said tracing wheel and said connections, said joint providing means for adjusting said tracing wheel and said traction wheel into predetermined angular relation.

7. A guiding unit as claimed in claim 6, including a protractor scale and an index operative between said column and said support to indicate the swiveling motion of said column, and means for adjusting the zero position of said scale to various angular positions of said traction wheel.

8. A reproducing machine guiding unit for controlling the motion of a reproducing machine tool-supporting carriage in varying directions in a plane, said guiding unit comprising manuallyadjustable steering means for guiding said carriage; angle-selector means fixed to said steering means in the normal position but movable relatively to said steering means from said normal position through a selected angle; and indexing means adapted to lock said steering means to said angle-selector means when said steering means is shifted through said selected angle to restore said normal position.

9. A reproducing machine guiding unit for controlling the motion of a reproducing machine tool-supporting carriage in varying directions in a plane, said guiding unit comprising manuallyadiustable steering means for guiding said carriage; and angle-selector means adapted to be set at a predetermined angle relative to an initial position of said steering means without disturbing the position of said steering means, said angle-selector means including registering means cooperable with said steering means and adapt ed to stop further motion of said steering means when said steering means are shifted through said predetermined angle from said initial position to a new position.

10. A reproducing machine guiding unit for controlling the motion of a reproducing machine tool-supporting carriage in varying'directions in a plane, said guiding unit comprising manuallyadjustable steering means for guiding said carriage; angle-selector means adapted to be set at a predetermined angle relative to an initial position of said steering means without disturbing the position of said steering means. said angleselector means including registering means cooperable with said steering means and adapted to stop further motion of said steering means when said steering means are shifted to a new position through said predetermined angle: and means for automatical y shiftin said steering means from said initial position throu h said predetermined angle until said steering means reaches said new position.

11. A reproducing machine guiding unit for controlling the motion of a reproducing-machine tool-supporting carriage in varying directions in a plane, said guiding unit comprising a support mounted on said carriage; steering means on said support and swingable through an arc to control the angle of movement of said carriage; a lock to secure said steering means in predetermined position relative to said support for providing carriage motion in a predetermined direction; and an adjustable angle selector having registering means adapted to locate said selector and steering means in predetermined normal angular position relative to one another, but being free, even while said steering means is locked, to move from said normal position to a new position through a selected arc determined by the desired change of angle of carriage motion; and means for locking said angle selector in said new position; said steering meansbeing free, when unlocked, to be swung through said selected are and to cooperate with said registering means to restore said normal position, said angle selector thereby setting said steering means in a new position to change the angle of movement of said carriage.

12. A reproducing machine guiding unit as claimed in claim 11 including means for urging said steering-means lock into the engaging po- Sl'tiUn.

13. A reproducing machine guiding unit for controlling the motion of a reproducing-machine tool-supporting carriage in varying directions in a plane, said'guiding unit comprising a support mounted on said carriage; steering means on said support and swingable through an arc to control the angle of movement of said carriage; a lock to secure said steering means'in predetermined position relative to said support for providing carriage motion in a predetermined direction; and an adjustable angle selector having registering means adapted to locate said selector and steering means in predetermined normal angular position relative to one another, but being free, even while said steering means is locked, to move from said normal position to a new position through a selected arc determined by the desired change of angle of carriage motion; means for locking said angle selector in said new position; said steering means being free, when un locked, to be swung through said selected are and to cooperate with said registering means to restore said normal position, said angle selector thereby setting said steering means in a new position to change the angle of movement of said carr ge; and means operable when said steering means is unlocked for automatically swinging said steering means through said selected are to said normal position, thereby setting said steering means in a new position to change the angle of movement of said carriage.

14. A traction-head guiding unit for reproducing machines of the type having a tool-supporting carriage relatively movable in varying directions along a traction surface by a steerable traction wheel rotatably mounted on said head for rolling engagement with said surface, said guiding unit comprising a support on said carriage in spaced relation to said head; a guide wheel journalled relative to said support for free rolling contact along said surface; manually operable steering means for steering said guide wheel along a predetermined course; interlocking connections between said guide wheel and said traction wheel to transmit the steering moaaaaesa tion of said guide wheel to said traction wheel, whereby both of said wheels are steered in unison to guide said carriage along a path defined by said course; and a prqtractor scale denoting the direction of carr age travel.

15. A reprodilt g machine guiding unit for controlling the mot on of a reproducing machine tool-supporting carriage" movable in a plane when said steeringmeans is shifted through said selected angle to restore said normal position; and cooperative scale and index means between said support and said angle-selector means for indicating the angular position ofsaid steering means relative to one of said coordinates when said angle-selector means and said steering means are in said normal position.

16. A reproducing machine guiding unit for controlling the motion of a reproducing machine tool-supporting carriage in varying directions in a plane, said guiding unit comprising manuallyadiustable steering means for guiding said carriage; angle-selector means fixed to said steering means in the normal position but movable relatively to said steering means from said normal position through a selected angle, said angle-selector means including a protractor and index movable relatively to one another; and indexing means adapted to lock said steering means to said angle-selector means when said steering means is shifted through said selected angle to restore said normal position.

17. A traction head guiding unit as claimed in claign 5 wherein said guide wheel is freely slida-ble relative to said support along a line perpendicular to said surface, said unit including means for urging said wheel into rolling contact with said surface. Q

18. In a reproducing machine having a carriage and means for propelling said carriage in selected directions, means for reproducing a angle and distance of carriage movement, which comprises means movable with respect to a relatively stationary part of said carriage for selecting and maintaining a first direction of carriage movement, an odometer on said relatively stationary part of said carriage for indicating the distance of carriage travel in said first direction, said selecting means being operable to select and maintain a second direction of carriage movement, and said odometer being operable to indicate the distance of carriage travel in said second direction, whereby successive angles and sides may be reproduced from the dimensions thereof.

19. In a reproducing machine having a carriage and means for propelling said carriage in selected directions, means for reproducing a polygonal outline which comprises means movable with respect to a relatively stationary part of said carriage for selecting and maintaining the direction of carriage propulsion, an odometer on said relatively stationary part of said carriage for indicating the distance of carriage travel, said selecting means being operable to select and maintain a second direction, and said odometer being operable to indicate the distance of carriage travel in said second direction, and means for starting and stopping said carriage propelling means whereby said propelling means may be started at the beginning of said carriage propulsion in each of said directions and whereby the same may be stopped at the end of the carriage travel in that direction.

20. A tracing unit for a reproducinymachine carriage supported for movement in varying directions in a substantially horizontal plane, said unit comprising a wheel adapted to roll on a templet surface;

swivelled with respect to said carriage for directing the movement of said wheel in varying directions in said plane, a bearing for rotatably receiving said wheel, and a bearing support, said wheel-mounting means including adjustable means for locking said bearing support at predetermined elevations relative to said steering column, said bearing support being provided with a slidable connection permitting a predetermined degree of vertical floating movement of said bearing and said wheel relative to said hearing support; and resilient means operative on said bearing to urge said bearing downwardly to the lower extreme position of the range of said floating movement.

21. In a reproducing machine having a cargiage and means for propelling said carriage in and wheel-mounting means comprising a manually pivotal steering column selected directions, means movable by said carriage for reproducing a pattern consisting of intersecting-lines which comprises means for selecting and maintaining a first direction of carriage propulsion parallel to one of said lines, an odometer for indicating the distance of carriage travel in said first direction, said selecting means being operable during said travel in said first direction to preset a second direction of carriage travel parallel to another of said lines whereby, upon completion of said first distance of carriage travel indicated by said odometer, said selecting means may be set to said preset direction before starting along the second direction of travel.

22. Means for guiding and controlling a tracer to travel along a pattern consisting of intersecting lines, which comprises means for selecting and maintaining a first direction of tracer travel along one of said lines, means for indicating the distance of tracer travel in said first direction, said selecting means being operable during said travel in said first direction to preset a second direction of tracer travel along another'of said lines whereby, upon completion of said first distance of tracer travel as indicated by said indicating means, said selecting means may be rapidly set to said preset direction, thereby selecting and maintaining said second direction of tracer travel.

FRANK C. GEIBIG. 

